diff --git a/index.js b/index.js
index d41b2378..85a0330c 100644
--- a/index.js
+++ b/index.js
@@ -523,7 +523,7 @@ function session(options) {
  * @private
  */
 
-function generateSessionId(sess) {
+function generateSessionId() {
   return uid(24);
 }